gecko-dev/xpcom/io/nsIFile.idl

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "nsISupports.idl"
#include "nsIDirectoryEnumerator.idl"

%{C++
struct PRFileDesc;
struct PRLibrary;
#include <stdio.h>
#include "mozilla/Path.h"
#include "nsCOMPtr.h"
#include "nsStringFwd.h"
namespace mozilla {
using PathString = nsTString<filesystem::Path::value_type>;
using PathSubstring = nsTSubstring<filesystem::Path::value_type>;
} // namespace mozilla
%}

[ptr] native PRFileDescStar(PRFileDesc);
[ptr] native PRLibraryStar(PRLibrary);
[ptr] native FILE(FILE);
native PathString(mozilla::PathString);

/**
 * An nsIFile is an abstract representation of a filename. It manages
 * filename encoding issues, pathname component separators ('/' vs. '\\'
 * vs. ':') and weird stuff like differing volumes with identical names, as
 * on pre-Darwin Macintoshes.
 *
 * This file has long introduced itself to new hackers with this opening
 * paragraph:
 *
 *    This is the only correct cross-platform way to specify a file.
 *    Strings are not such a way. If you grew up on windows or unix, you
 *    may think they are.  Welcome to reality.
 *
 * While taking the pose struck here to heart would be uncalled for, one
 * may safely conclude that writing cross-platform code is an embittering
 * experience.
 *
 * All methods with string parameters have two forms.  The preferred
 * form operates on UCS-2 encoded characters strings.  An alternate
 * form operates on characters strings encoded in the "native" charset.
 *
 * A string containing characters encoded in the native charset cannot
 * be safely passed to javascript via xpconnect.  Therefore, the "native
 * methods" are not scriptable.
 */
[scriptable, main_process_scriptable_only, uuid(2fa6884a-ae65-412a-9d4c-ce6e34544ba1), builtinclass]
interface nsIFile : nsISupports
{
    /**
     *  Create Types
     *
     *  NORMAL_FILE_TYPE - A normal file.
     *  DIRECTORY_TYPE   - A directory/folder.
     */
    const unsigned long NORMAL_FILE_TYPE = 0;
    const unsigned long DIRECTORY_TYPE   = 1;

    /**
     *  append[Native]
     *
     *  This function is used for constructing a descendent of the
     *  current nsIFile.
     *
     *   @param node
     *       A string which is intended to be a child node of the nsIFile.
     *       For the |appendNative| method, the node must be in the native
     *       filesystem charset.
     */
    void append(in AString node);
    [noscript] void appendNative(in ACString node);

    /**
     *  Normalize the pathName (e.g. removing .. and . components on Unix).
     */
    void normalize();

    /**
     *  create
     *
     *  This function will create a new file or directory in the
     *  file system. Any nodes that have not been created or
     *  resolved, will be.  If the file or directory already
     *  exists create() will return NS_ERROR_FILE_ALREADY_EXISTS.
     *
     *   @param type
     *       This specifies the type of file system object
     *       to be made.  The only two types at this time
     *       are file and directory which are defined above.
     *       If the type is unrecongnized, we will return an
     *       error (NS_ERROR_FILE_UNKNOWN_TYPE).
     *
     *   @param permissions
     *       The unix style octal permissions.  This may
     *       be ignored on systems that do not need to do
     *       permissions.
     */
    [must_use] void create(in unsigned long type, in unsigned long permissions);

    /**
     *  Accessor to the leaf name of the file itself.
     *  For the |nativeLeafName| method, the nativeLeafName must
     *  be in the native filesystem charset.
     */
    attribute AString leafName;
    [noscript] attribute ACString nativeLeafName;

    /**
     *  copyTo[Native]
     *
     *  This will copy this file to the specified newParentDir.
     *  If a newName is specified, the file will be renamed.
     *  If 'this' is not created we will return an error
     *  (NS_ERROR_FILE_TARGET_DOES_NOT_EXIST).
     *
     *  copyTo may fail if the file already exists in the destination
     *  directory.
     *
     *  copyTo will NOT resolve aliases/shortcuts during the copy.
     *
     *   @param newParentDir
     *       This param is the destination directory. If the
     *       newParentDir is null, copyTo() will use the parent
     *       directory of this file. If the newParentDir is not
     *       empty and is not a directory, an error will be
     *       returned (NS_ERROR_FILE_DESTINATION_NOT_DIR). For the
     *       |CopyToNative| method, the newName must be in the
     *       native filesystem charset.
     *
     *   @param newName
     *       This param allows you to specify a new name for
     *       the file to be copied. This param may be empty, in
     *       which case the current leaf name will be used.
     */
    void copyTo(in nsIFile newParentDir, in AString newName);
    [noscript] void CopyToNative(in nsIFile newParentDir, in ACString newName);

    /**
     *  copyToFollowingLinks[Native]
     *
     *  This function is identical to copyTo with the exception that,
     *  as the name implies, it follows symbolic links.  The XP_UNIX
     *  implementation always follow symbolic links when copying.  For
     *  the |CopyToFollowingLinks| method, the newName must be in the
     *  native filesystem charset.
     */
    void copyToFollowingLinks(in nsIFile newParentDir, in AString newName);
    [noscript] void copyToFollowingLinksNative(in nsIFile newParentDir, in ACString newName);

    /**
     *  moveTo[Native]
     *
     *  A method to move this file or directory to newParentDir.
     *  If a newName is specified, the file or directory will be renamed.
     *  If 'this' is not created we will return an error
     *  (NS_ERROR_FILE_TARGET_DOES_NOT_EXIST).
     *  If 'this' is a file, and the destination file already exists, moveTo
     *  will replace the old file.
     *  This object is updated to refer to the new file.
     *
     *  moveTo will NOT resolve aliases/shortcuts during the copy.
     *  moveTo will do the right thing and allow copies across volumes.
     *  moveTo will return an error (NS_ERROR_FILE_DIR_NOT_EMPTY) if 'this' is
     *  a directory and the destination directory is not empty.
     *  moveTo will return an error (NS_ERROR_FILE_ACCESS_DENIED) if 'this' is
     *  a directory and the destination directory is not writable.
     *
     *   @param newParentDir
     *       This param is the destination directory. If the
     *       newParentDir is empty, moveTo() will rename the file
     *       within its current directory. If the newParentDir is
     *       not empty and does not name a directory, an error will
     *       be returned (NS_ERROR_FILE_DESTINATION_NOT_DIR).  For
     *       the |moveToNative| method, the newName must be in the
     *       native filesystem charset.
     *
     *   @param newName
     *       This param allows you to specify a new name for
     *       the file to be moved. This param may be empty, in
     *       which case the current leaf name will be used.
     */
    void moveTo(in nsIFile newParentDir, in AString newName);
    [noscript] void moveToNative(in nsIFile newParentDir, in ACString newName);

    /**
     *  moveToFollowingLinks[Native]
     *
     *  This function is identical to moveTo with the exception that,
     *  as the name implies, it follows symbolic links.  The XP_UNIX
     *  implementation always follows symbolic links when moving.  For
     *  the |MoveToFollowingLinks| method, the newName ust be in the native
     *  filesystem charset.
     */
    void moveToFollowingLinks(in nsIFile newParentDir, in AString newName);
    [noscript] void moveToFollowingLinksNative(in nsIFile newParentDir, in ACString newName);

    /**
     *  renameTo
     *
     *  This method is identical to moveTo except that if this file or directory
     *  is moved to a a different volume, it fails and returns an error
     *  (NS_ERROR_FILE_ACCESS_DENIED).
     *  This object will still point to the old location after renaming.
     */
    void renameTo(in nsIFile newParentDir, in AString newName);
    [noscript] void renameToNative(in nsIFile newParentDir, in ACString newName);

    /**
     *  This will try to delete this file.  The 'recursive' flag
     *  must be PR_TRUE to delete directories which are not empty.
     *
     *  This will not resolve any symlinks.
     */
    void remove(in boolean recursive);

    /**
     *  Attributes of nsIFile.
     */

    attribute unsigned long permissions;
    attribute unsigned long permissionsOfLink;

    /**
     *  File Times are to be in milliseconds from
     *  midnight (00:00:00), January 1, 1970 Greenwich Mean
     *  Time (GMT).
     */
    attribute PRTime lastModifiedTime;
    attribute PRTime lastModifiedTimeOfLink;

    /**
     * The creation time of file in milliseconds from midnight, January 1, 1970
     * GMT, if available.
     *
     * This attribute is only implemented on Windows and macOS. Accessing this
     * on another platform will this will throw NS_ERROR_NOT_IMPLEMENTED.
     */
    readonly attribute PRTime creationTime;
    readonly attribute PRTime creationTimeOfLink;

    /**
     *  WARNING!  On the Mac, getting/setting the file size with nsIFile
     *  only deals with the size of the data fork.  If you need to
     *  know the size of the combined data and resource forks use the
     *  GetFileSizeWithResFork() method defined on nsILocalFileMac.
     */
    attribute int64_t fileSize;
    readonly attribute int64_t fileSizeOfLink;

    /**
     *  target & path
     *
     *  Accessor to the string path.  The native version of these
     *  strings are not guaranteed to be a usable path to pass to
     *  NSPR or the C stdlib.  There are problems that affect
     *  platforms on which a path does not fully specify a file
     *  because two volumes can have the same name (e.g., mac).
     *  This is solved by holding "private", native data in the
     *  nsIFile implementation.  This native data is lost when
     *  you convert to a string.
     *
     *      DO NOT PASS TO USE WITH NSPR OR STDLIB!
     *
     *  target
     *      Find out what the symlink points at.  Will give error
     *      (NS_ERROR_FILE_INVALID_PATH) if not a symlink.
     *
     *  path
     *      Find out what the nsIFile points at.
     *
     *  Note that the ACString attributes are returned in the
     *  native filesystem charset.
     *
     */
    readonly attribute AString target;
    [noscript] readonly attribute ACString nativeTarget;
    readonly attribute AString path;
    [notxpcom,nostdcall,must_use] PathString nativePath();
%{C++
#ifndef XP_WIN
    nsresult GetNativePath(nsACString& aPath);
#endif
    /*
     * Returns a human-readable path string.
     */
    nsCString HumanReadablePath();
%}

    boolean exists();
    boolean isWritable();
    boolean isReadable();
    boolean isExecutable();
    boolean isHidden();
    boolean isDirectory();
    boolean isFile();
    boolean isSymlink();
    /**
     * Not a regular file, not a directory, not a symlink.
     */
    boolean isSpecial();

    /**
     *  createUnique
     *
     *  This function will create a new file or directory in the
     *  file system. Any nodes that have not been created or
     *  resolved, will be.  If this file already exists, we try
     *  variations on the leaf name "suggestedName" until we find
     *  one that did not already exist.
     *
     *  If the search for nonexistent files takes too long
     *  (thousands of the variants already exist), we give up and
     *  return NS_ERROR_FILE_TOO_BIG.
     *
     *   @param type
     *       This specifies the type of file system object
     *       to be made.  The only two types at this time
     *       are file and directory which are defined above.
     *       If the type is unrecongnized, we will return an
     *       error (NS_ERROR_FILE_UNKNOWN_TYPE).
     *
     *   @param permissions
     *       The unix style octal permissions.  This may
     *       be ignored on systems that do not need to do
     *       permissions.
     */
    [must_use]
    void createUnique(in unsigned long type, in unsigned long permissions);

    /**
      * clone()
      *
      * This function will allocate and initialize a nsIFile object to the
      * exact location of the |this| nsIFile.
      *
      *   @param file
      *          A nsIFile which this object will be initialize
      *          with.
      *
      */
    nsIFile clone();

    /**
     *  Will determine if the inFile equals this.
     */
    boolean equals(in nsIFile inFile);

    /**
     *  Will determine if inFile is a descendant of this file.
     *  This routine looks in subdirectories too.
     */
    boolean contains(in nsIFile inFile);

    /**
     *  Parent will be null when this is at the top of the volume.
     */
    readonly attribute nsIFile parent;

    /**
     *  Returns an enumeration of the elements in a directory. Each
     *  element in the enumeration is an nsIFile.
     *
     *   @throws NS_ERROR_FILE_NOT_DIRECTORY if the current nsIFile does
     *           not specify a directory.
     */
    [binaryname(DirectoryEntriesImpl)]
    readonly attribute nsIDirectoryEnumerator directoryEntries;

    %{C++
    nsresult GetDirectoryEntries(nsIDirectoryEnumerator** aOut)
    {
      return GetDirectoryEntriesImpl(aOut);
    };
    %}

    /**
     *  initWith[Native]Path
     *
     *  This function will initialize the nsIFile object.  Any
     *  internal state information will be reset.
     *
     *   @param filePath
     *       A string which specifies a full file path to a
     *       location.  Relative paths will be treated as an
     *       error (NS_ERROR_FILE_UNRECOGNIZED_PATH).  For
     *       initWithNativePath, the filePath must be in the native
     *       filesystem charset.
     */
    void initWithPath(in AString filePath);
    [noscript] void initWithNativePath(in ACString filePath);

    /**
     *  initWithFile
     *
     *  Initialize this object with another file
     *
     *   @param aFile
     *       the file this becomes equivalent to
     */
    void initWithFile(in nsIFile aFile);

    /**
     * Flag for openNSPRFileDesc(), to hint to the OS that the file will be
     * read sequentially with agressive readahead.
     */
    const unsigned long OS_READAHEAD = 0x40000000;

    /**
     * Flag for openNSPRFileDesc(). Deprecated and unreliable!
     * Instead use NS_OpenAnonymousTemporaryFile() to create a temporary
     * file which will be deleted upon close!
     */
    const unsigned long DELETE_ON_CLOSE = 0x80000000;

    /**
     * Return the result of PR_Open on the file.  The caller is
     * responsible for calling PR_Close on the result.  On success, the
     * returned PRFileDescr must be non-null.
     *
     * @param flags the PR_Open flags from prio.h, plus optionally
     * OS_READAHEAD or DELETE_ON_CLOSE. OS_READAHEAD is a hint to the
     * OS that the file will be read sequentially with agressive
     * readahead. DELETE_ON_CLOSE is unreliable on Windows and is deprecated.
     * Instead use NS_OpenAnonymousTemporaryFile() to create a temporary
     * file which will be deleted upon close.
     */
    [noscript, must_use] PRFileDescStar openNSPRFileDesc(in long flags,
                                                         in long mode);

    /**
     * Return the result of fopen on the file.  The caller is
     * responsible for calling fclose on the result.  On success, the
     * returned FILE pointer must be non-null.
     */
    [noscript, must_use] FILE openANSIFileDesc(in string mode);

    /**
     * Return the result of PR_LoadLibrary on the file.  The caller is
     * responsible for calling PR_UnloadLibrary on the result.
     */
    [noscript, must_use] PRLibraryStar  load();

    // number of bytes available on disk to non-superuser
    [must_use] readonly attribute int64_t diskSpaceAvailable;

    /**
     *  appendRelative[Native]Path
     *
     *  Append a relative path to the current path of the nsIFile object.
     *
     *   @param relativeFilePath
     *       relativeFilePath is a native relative path. For security reasons,
     *       this cannot contain .. or cannot start with a directory separator.
     *       For the |appendRelativeNativePath| method, the relativeFilePath
     *       must be in the native filesystem charset.
     */
    void appendRelativePath(in AString relativeFilePath);
    [noscript] void appendRelativeNativePath(in ACString relativeFilePath);

    /**
     *  Accessor to a null terminated string which will specify
     *  the file in a persistent manner for disk storage.
     *
     *  The character set of this attribute is undefined.  DO NOT TRY TO
     *  INTERPRET IT AS HUMAN READABLE TEXT!
     */
    [must_use] attribute ACString persistentDescriptor;

    /**
     *  reveal
     *
     *  Ask the operating system to open the folder which contains
     *  this file or folder. This routine only works on platforms which
     *  support the ability to open a folder and is run async on Windows.
     *  This routine must be called on the main.
     */
    [must_use] void reveal();

    /**
     *  launch
     *
     *  Ask the operating system to attempt to open the file.
     *  this really just simulates "double clicking" the file on your platform.
     *  This routine only works on platforms which support this functionality
     *  and is run async on Windows.  This routine must be called on the
     *  main thread.
     */
    [must_use] void launch();

    /**
     *  getRelativeDescriptor
     *
     *  Returns a relative file path in an opaque, XP format. It is therefore
     *  not a native path.
     *
     *  The character set of the string returned from this function is
     *  undefined.  DO NOT TRY TO INTERPRET IT AS HUMAN READABLE TEXT!
     *
     *   @param fromFile
     *       the file from which the descriptor is relative.
     *       Throws if fromFile is null.
     */
    [must_use] ACString getRelativeDescriptor(in nsIFile fromFile);

    /**
     *  setRelativeDescriptor
     *
     *  Initializes the file to the location relative to fromFile using
     *  a string returned by getRelativeDescriptor.
     *
     *   @param fromFile
     *       the file to which the descriptor is relative
     *   @param relative
     *       the relative descriptor obtained from getRelativeDescriptor
     */
    [must_use]
    void setRelativeDescriptor(in nsIFile fromFile, in ACString relativeDesc);

    /**
     *  getRelativePath
     *
     *  Returns a relative file from 'fromFile' to this file as a UTF-8 string.
     *  Going up the directory tree is represented via "../".  '/' is used as
     *  the path segment separator.  This is not a native path, since it's UTF-8
     *  encoded.
     *
     *   @param fromFile
     *       the file from which the path is relative.
     *       Throws if fromFile is null.
     */
    [must_use] AUTF8String getRelativePath(in nsIFile fromFile);

    /**
     *  setRelativePath
     *
     *  Initializes the file to the location relative to fromFile using
     *  a string returned by getRelativePath.
     *
     *   @param fromFile
     *       the file from which the path is relative
     *   @param relative
     *       the relative path obtained from getRelativePath
     */
    [must_use]
    void setRelativePath(in nsIFile fromFile, in AUTF8String relativeDesc);
};

%{C++
#ifdef MOZILLA_INTERNAL_API
#include "nsDirectoryServiceUtils.h"
#include "nsString.h"

inline std::ostream& operator<<(std::ostream& aOut, const nsIFile& aFile) {
  nsIFile* file = const_cast<nsIFile*>(&aFile);
  nsAutoString path;
  file->GetPath(path);
  return aOut << "nsIFile { " << path << " }";
}
#endif
%}